EP3970645A1

EP3970645A1 - Implant, insertion device and plate assembly

Info

Publication number: EP3970645A1
Application number: EP20197497.9A
Authority: EP
Inventors: Timo Biedermann; Tobias Hägle
Original assignee: Biedermann Technologies GmbH and Co KG
Current assignee: Biedermann Technologies GmbH and Co KG
Priority date: 2020-09-22
Filing date: 2020-09-22
Publication date: 2022-03-23
Anticipated expiration: 2040-09-22
Also published as: JP7616974B2; CN114246710A; US12208016B2; US20220087830A1; US20250186216A1; JP2022051708A; EP3970645B1

Abstract

An implant, in particular a spinal implant and more particularly an intervertebral implant or a placeholder for vertebrae or portions thereof, includes a body insertable into space between two bone parts or vertebrae or portions thereof, the body comprising a first face (5a), a second face (5a) connected to and opposite to the first face, wherein the body comprises at least one connection portion (10, 10', 30, 30') for connecting the spinal implant (1, 1'. 1") to a holding member (110, 210, 330) of an insertion device (100, 200) for the implant or a secondary device such as a plate member (310), wherein the connection portion (10, 10', 30, 30') comprises a hollow space defined by the body between the first and second faces configured to accommodate an engagement portion (118, 118'; 218; 338) of the holding member, the hollow space being accessible from outside the body though an opening (11, 31) formed between the first and second faces; wherein the opening (11, 31) is elongate such that the engagement portion of the holding device is insertable into the hollow space through the opening when the engagement portion has a first orientation and is prevented from removal from the hollow space when the engagement portion is in a second orientation; and wherein the connection portion (10, 10', 30, 30') is located on the implant and configured in such a way that it permits to selectively connect at least two different holding members (110, 210, 330) to the implant.

Description

The invention relates to an implant, in particular to a spinal implant, an insertion device for such an implant and a plate assembly. The implant may be, for example, an intervertebral implant for intervertebral disc replacement in the case of a damaged intervertebral disc or a placeholder for bridging the space of a removed vertebra following vertebrectomy.
In the case of damaged intervertebral discs, lumbar or thoracic interbody fusion surgery is one of the most commonly performed instrumented spinal fusion surgeries. Among others, known surgical approaches for interbody fusion of the lumbar spine include posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), anterior lumbar interbody fusion (ALIF), antero-lateral ALIF and lateral interbody fusion as well as oblique lateral interbody fusion.
An intervertebral implant and a device for inserting the same that are, for example, suitable for TLIF are described in US 2017/0056194 A1 . The intervertebral implant comprises a top surface, a bottom surface, and a sidewall extending between the top surface and the bottom surface and a hollow space formed within the intervertebral implant and accessible through an elongate opening extending through a recessed portion of the sidewall. The hollow space is shaped to receive an engagement portion of a drive shaft of an insertion tool. The intervertebral implant includes at least two guiding surfaces facing each other and being configured for sliding engagement by a portion of a sleeve of the insertion tool movably holding the drive shaft.
US 2016/0235546 A1 describes a spacer with temporary fixation which includes the spacer, a plate, an attachment member and a temporary fixation screw. The temporary fixation of the spacer is applicable in a lateral spinal procedure to prevent migration of the spacer while a patient is being rotated after insertion of the spacer.
It is an object underlying the invention to provide an improved or alternative implant, an insertion device therefor, and a fixation device, and systems including the implant and an insertion device or a fixation device such as a plate assembly that are versatile and simple in use and have an enlarged field of application.
The object is solved by an implant according to claim 1, by an insertion device according to claim 9, by a plate assembly according to claim 12 and by systems according to claims 11 or 14. Further developments are given in the dependent claims. The further developments as described in the dependent claims of a particular independent claim are also applicable to the other independent claims, even if not explicitly stated.
According to an embodiment in implant, in particular a spinal implant, for example an intervertebral implant or a placeholder for vertebrae includes a body insertable into the space between two bones or bone parts, more particularly between two vertebrae, the body comprising a first face, a second face connected to and opposite to the first face, wherein the body comprises at least one connection portion for connecting the spinal implant to a holding member of an insertion device for the implant or a secondary device such as a plate member. The connection portion comprises a hollow space defined by the body between the first and second faces configured to accommodate an engagement portion of the holding member, the hollow space being accessible from outside the body through an opening formed between the first and second faces. The opening is elongate with a length that is greater than a width in at least a portion thereof such that the engagement portion of the holding member is insertable into the hollow space through the opening when the engagement portion has a first orientation and is prevented from removal from the hollow space when the engagement portion is in a second orientation; and wherein the connection portion is located on the implant and configured in such a way that it permits to selectively connect at least two different holding to the implant.
The connection portion of the implant, in particular the spinal implant is multi-functional. It is designed such that a holding portion of a further device, such as an insertion instrument or a plate member, which is adapted to cooperate with the connection portion can be inserted and tilted whereafter it is prevented from removal. In addition, other instruments, such as a different insertion device which is suitable for a different surgical insertion approach, may be connected to the implant using the connection portion in a different manner.
The connection is threadless which renders it robust and easy to establish, disconnect and reconnect.
The implant, in particular the spinal implant may be an intervertebral implant for disc replacement or a placeholder for bridging the gap in case of removal of one or more vertebrae or portions thereof.
Due to the increase in functionality, the implant may be particularly useful in the case of difficult anatomical circumstances such as an anterior and lateral approaches to the spine as well as revision surgery.
According to a further embodiment, an insertion device for inserting the implant described above comprises two holding members each having an engagement portion wherein the holding members form a fork-shaped holding portion of the insertion device and wherein the engagement portions are configured to engage connection portions provided at opposite corners of the implant, respectively. The holding members are configured to move from a first configuration in which the engagement portions have a first distance from each other to a second configuration in which the engagement portions have a second distance from each other smaller than the first distance. A sleeve may be provided around the holding members which is displaceable relative to the holding members such as to move them from the first configuration to the second configuration.
With such an insertion device the implant, in particular the spinal implant, most suitable an intervertebral implant, may be engaged in a clamp like manner and fixed by the instrument. The implant may then be inserted, for example, in an anterior approach.
According to a further embodiment, a plate assembly comprises a plate member and a holding member connectable to the plate member wherein the holding member comprises an engagement portion that is configured to engage the connection portion of the spinal implant in a threadless manner. In particular, the plate member may be used as a temporary fixation plate which can provide temporary stability to the spinal region which comprises the implant.
The threadless connection may also permit the plate member to assume various angular positions relative to the implant, in particular the spinal implant.
According to a still further embodiment, the implant, in particular the spinal implant comprises a tube member with openings therein which is intended to form a placeholder for one or more removed vertebrae or portions thereof. The hollow space of the connection portion is formed inside the tube.
According to a still further embodiment, a kit of an implant, in particular a spinal implant as described above with at least two devices out of a group comprising at least two different insertion devices as described hereinafter and a plate assembly.
Further features and advantages will become apparent from the detailed description of embodiment by means of the accompanying drawings. In the drawings:

Fig. 1:: shows a perspective view of a first embodiment of a spinal implant in the form of an intervertebral implant, in particular for the ALIF-procedure and/or antero-lateral ALIF procedure, and a first insertion device therefor.
Fig. 2:: shows a perspective view from the top of the intervertebral implant of Fig. 1.
Fig. 3: shows a perspective view from the bottom of the intervertebral implant of Figs. 1 and 2.
Fig. 4:: shows a front view of the intervertebral implant of Figs. 1 to 3.
Fig. 5:: shows a cross-sectional view of the intervertebral implant of Figs. 1 to 4 along line A-A in Fig. 4.
Fig. 6:: shows a perspective view from the top of a holding portion of the insertion device of Fig. 1.
Fig. 7:: shows a perspective view from the bottom of the holding portion of Fig. 6.
Fig. 8:: shows a top view of the holding portion of Figs. 6 and 7.
Fig. 9:: shows a perspective view of a step of orienting the insertion device and the intervertebral implant of Figs. 1 to 8 relative to each other for connecting them.
Fig. 10:: shows a perspective view of a step of engaging the intervertebral implant to Fig. 9 with the insertion device.
Figs. 11a to 11d:: show cross-sectional views of steps of engaging the intervertebral implant with the insertion device according to the previous Figures and locking the intervertebral implant relative to the insertion device.
Fig. 12:: shows the intervertebral implant as depicted in Figs. 1 to 11d with a second embodiment of an insertion device in a first mode of connection.
Fig. 13:: shows a perspective view of the intervertebral implant and insertion device of Fig. 12 in a second mode of connection.
Fig. 14:: shows a perspective view from above of a front portion of a holding member of the insertion device of Figs. 12 and 13.
Fig. 15:: shows a side view of the holding member of Fig. 14.
Fig. 16:: shows a side view of the holding member of Figs. 14 and 15.
Fig. 17:: shows a perspective view of a front portion of a locking sleeve of the insertion device of Figs. 12 and 13.
Fig. 18:: shows a side view of the locking sleeve of Fig. 17.
Fig. 19:: shows a top view of the locking sleeve of Figs. 17 and 18.
Fig. 20:: shows a perspective view of a step of orienting the intervertebral implant and the insertion device of Figs. 12 to 19 relative to each other.
Fig. 21:: shows a second step of engaging the intervertebral implant with the insertion device of Fig. 12.
Figs. 22a to 22d:: show cross-sectional views of of engaging the intervertebral implant as shown inFig. 12 with the insertion device as shown in Fig. 12 in the first mode of connection in various pivot positions of the intervertebral implant relative to the insertion device.
Fig. 22e:: shows a cross-sectional view of engaging the intervertebral implant as shown in Fig. 13 with the insertion device as shown in Fig. 13 in the second mode of connection.
Fig. 23:: shows an exploded perspective view of the intervertebral implant of Figs. 1 to 22d together with a plate assembly.
Fig. 24:: shows the intervertebral implant and the plate assembly of Fig. 23 in an assembled configuration.
Fig. 25:: shows a perspective view from the top onto the plate member of the plate assembly of Figs. 23 and 24.
Fig. 26:: shows a perspective view from the bottom of the plate member of Figs. 23 to 25.
Fig. 27:: shows a top view of the plate member of Figs. 23 to 26.
Fig. 28:: shows a cross-sectional view of the plate member of Figs. 23 to 27 along line B-B in Fig. 27.
Fig. 29:: shows a perspective view from the top onto a holding member of the plate assembly of Figs. 23 and 24.
Fig. 30:: shows a side view of the holding member of Fig. 29.
Fig. 31:: shows a top view of the holding member of Figs. 29 and 30.
Fig. 32:: shows a perspective view from the top onto a locking member of the plate assembly of Figs. 23 and 24.
Fig. 33:: shows a perspective view from the bottom of the locking member of Fig. 32.
Fig. 34:: shows a perspective view from the top of a sleeve member of the plate assembly of Figs. 23 and 24.
Fig. 35:: shows a perspective view from the bottom of the sleeve member of Fig. 34.
Fig. 36:: shows a top view of the sleeve member of Figs. 34 and 35.
Fig. 37:: shows a cross-sectional view of the sleeve member of Figs. 34 to 36 along line D-D in Fig. 36.
Fig. 38:: shows a perspective view of the plate assembly of Figs. 23 and 24 with other embodiment of a spinal implant in the form of another intervertebral implant.
Fig. 39:: shows a perspective view of a still further embodiment of a spinal implant with an insertion device, the implant being a placeholder, for example used following vertebrectomy.
Fig. 40:: shows an enlarged perspective view of a portion of Fig. 39.
Fig. 41:: shows a perspective view of the placeholder of Figs. 39 and 40 together with the plate assembly of Figs. 23 and 24.

Fig. 1 shows a perspective view of a spinal implant in the form of an intervertebral implant 1 and an insertion device 100 for inserting the intervertebral implant 1 into an intervertebral space. The intervertebral implant 1 shown in the Figures may be used in particular for anterior lumbar interbody fusion (ALIF). However, the embodiment is not limited to such type of intervertebral implant. Referring in addition in more detail to Figs. 2 to 5, the intervertebral implant 1 has a body including a substantially vertical side wall 2. The side wall 2 is formed monolithically with an inner solid portion 3 and encloses one or more inner hollow spaces 4. The hollow spaces 4 are open towards an upper face 5a and a lower face 5b of the intervertebral implant 1.
In greater detail, the side wall 2 is formed by a front wall 2a, an opposite back wall 2b, a right side wall 2c, and a left side wall 2d, which are monolithically formed, such that the right and left side walls connect the front wall 2a and the back wall 2b with each other. The front wall 2a represents an anterior wall and the back wall 2b represents a posterior wall of the intervertebral implant 1. The front wall 2a and the back wall 2b may be longer than the right side wall 2c and the left side wall 2d, so that the intervertebral implant 1 may have an elongate outer contour. In the embodiment shown, the front wall 2a and the back wall 2b are substantially parallel to each other and define a longitudinal central axis LI of the intervertebral implant. Moreover, the front wall 2a and the back wall 2b may have different heights, such that the top face 5a and the bottom face 5b form an angle, resulting in the intervertebral implant 1 having a wedge shape. For example, the front wall 2a may have a height greater than that of the back wall 2b for the correction of lordosis.
Optionally, inner walls 6a, 6b may extend from the front wall 2a to the back wall 2b by means of which the hollow spaces 4 are separated from each other. In the embodiment shown, three such hollow spaces 4 are provided, however, the design of the intervertebral implant is not limited to this number. The inner walls 6a, 6b may by symmetric with respect to a sagittal plane S that extends vertically through the centers of the front wall 2a and the back wall 2b. The solid portion 3 extends from the front wall 2a to a distance from the back wall 2b and has a length in this direction such that connection portions in the form of recesses, as further described below, can be formed in a solid body 3 with depths sufficient for engagement with the insertion device 100. The hollow spaces 4 are configured to be filled with bone graft material or biologics. Further, engagement portions, for example teeth (not shown), may be provided in the upper face 5a and the lower face 5b of the intervertebral implant 1, which may facilitate penetration into the end plates of adjacent vertebral bodies.
At the corners that are formed by the transition of the front wall 2a to the left side wall 2b and to the right side wall 2c, recesses 10, 10', respectively are provided that each form an elongate opening 11 in the side wall 2. Each recess 10, 10' defines a connection portion for connection with a holding portion of an insertion device or a plate member.
The two recesses 10, 10' are mirror symmetrical with respect to the sagittal plane S and therefore in the following, only the recess 10 will be described in more detail while in the embodiment, the recess 10' at the opposite corner has a mirror symmetrical design. The recess 10 defines a hollow space within the intervertebral implant 1 for receiving a portion of the insertion device. The recess 10 extends into the solid portion 3 and forms a corner with an angle of slightly more than 90 therein. Thereby, left and right boundary walls 10a, 10b of the recess 10 form an angle of slightly more than 90 °, for example about up to 100°. The recess 10 and the opening 11 may be provided at a middle of the side wall 2 in the height direction. It shall be understood, that the angle may also be about or exactly 100°.
A width of the recess 10 in the height direction is such that an engagement portion of the insertion device 100 can be introduced in one orientation, but cannot be introduced in a tilted orientation. Top and bottom walls of the recess 10 may be planar, and may extend substantially parallel to each other and substantially perpendicular to the side wall 2. The opening 11 extends in a circumferential direction from the front wall 2a over the corner between the front wall 2a and the right side wall 2c into the right sidewall.
In the inside corner of the recess 10, a spherically-shaped recess 12 is formed that is configured to receive an engagement portion of the insertion device 100. As shown in more detail in Figs. 11c and 11d, a radius of the spherically-shaped recess 12 matches a radius of an outer surface of the engagement portion of the insertion device. An axis R extending through a center of the spherically-shaped recess 12 and parallel to the side wall 2 forms an axis of rotation and more specifically, a pivot axis that enables a pivotal movement between the intervertebral implant 1 and an engagement portion of an insertion device or a plate member as explained in more detail below. The boundary walls 10a, 10b that delimit the recess 10 at the end of the opening 11 in the circumferential direction may have a contour that is suitable for guiding engagement with the engagement portion. It may be, for example, substantially cylindrical. The boundary wall 10b is substantially perpendicular to the right side wall 2d and the boundary wall 10a extends at a slight angle to the front wall 2a in such a manner that an enlarged portion 10c may formed between the spherical recess 12 and the boundary wall 10a. By means of this, the insertion of the engagement portion of the insertion device may be facilitated.
In addition, the side wall 2 may have, in the region of the elongate opening 11, outer surfaces that are shaped to provide abutment surfaces for an insertion device to achieve a form-fit engagement and/or to provide guiding surfaces for pivotal movement of the insertion device. As depicted more in detail in Fig. 5, a first abutment surface 21 is provided around the lateral edge of the elongate opening that extends into the right side wall 2c. For the recess 10' the first abutment surface 21 is in the left sidewall 2d. The first abutment surface 21 may be substantially cylindrical with a cylinder axis substantially parallel to the axis of rotation R. A second substantially planar abutment surface 22 is provided around the opposite lateral edge of the elongate opening 11 that extends into the front wall 2a. Lastly, a third substantially planar abutment surface 23 may extend around substantially a center of the opening 11 and forms an angle of substantially 45° with the second abutment surface 22.
Optionally, the intervertebral implant 1 may include further connection portions in the side wall 2. In the embodiment shown, the intervertebral implant has additional recesses 30, 30' at the right side wall 2c and the left side wall 2d, respectively. Each recess 30, 30' defines an elongate opening 31 and comprises an inner spherically-shaped recess 32, permitting rotation of an inserted engagement portion therein. The recesses 30, 30' are each configured such that an engagement portion of a holding member of an insertion device or a plate member can be inserted in one orientation, but cannot be inserted in a tilted orientation. The connection portions 30, 30' permit only a single angle between the implant and the holding portion of the device to be attached. It shall be noted, that the connection portions 30, 30' may also be designed such as to allow a variation in the angle between the insertion device and the implant.
Optionally, one or more additional holes 40 may be provided in the front wall 2a. The additional holes may be threaded, to receive fixation screws (not shown) for additional fixation of the intervertebral implant 1 with respect to the adjacent vertebral bodies. The axes of the additional holes 40 may be inclined with respect to the top face 5a and the bottom face 5b so that fixation screws extending therethrough are configured to engage the end plates of the vertebral bodies, respectively.
It shall be noted that the number and position of the recesses and holes is not limited to the number and position shown in the embodiment but more or less recesses and holes may be provided and the positions may vary.
Turning now to Figures 1 and 6 to 8, the insertion device 100 will be described. The insertion device 100 includes a holding portion 110, a sleeve 120 configured to extend around the holding portion 110 and a handle 130 connected to the holding portion. The sleeve 120 defines a longitudinal axis of the insertion device 100. The holding portion 110 comprises two holding members 111, 111', the front portions 112, 112' of which form a fork-shaped clamp configured to engage the intervertebral implant 1. The holding members 111, 111' each comprise a longitudinal bar 113, 113', wherein the bars 113, 113' are connected at their rear end 114. From the rear end 114 a post 115 with a threaded end portion 116 extends. The front portions 112, 112' each include a cross-bar 117, 117' extending transverse to the longitudinal axis in an outward direction. From each outer end of the cross-bar 117, 117' an engagement portion 118, 118' extends in a direction substantially parallel to the longitudinal axis L. The cross-bars 117, 117' may have a substantially rectangular cross-section with a height that is preferably smaller than a height of the front wall 2a. The length of the cross-bars 117, 117' is such that the engagement portions 188, 118' can be inserted into the recesses 10, 10'.
The engagement portions 118, 118' have a substantially spherical segment-shaped end portion 119, 119' with upper and lower surfaces that are substantially flat and parallel to each other. An axis F perpendicular to the flat surfaces is substantially perpendicular to the longitudinal axis L. The outer surface of the spherical segment-shaped portions 199, 199' may have a small cylindrical portion 119b. Hence, the engagement portion 118, 118' and in particular the spherical-segment-shaped end portion 119, 119' have a flattened shape with a thickness slightly smaller than a vertical height of the elongate opening 11 to permit insertion of the engagement portion into the recess 10, 10'. Between the spherical segment-shaped end portions 119, 119' and the cross-bar 117, 117' the engagement portion 118, 118' comprises a narrowing section 119a, 119a' to provide a hook-like shape. The enlarged portion 10c may facilitate .the engagement of the engagement portion with the recess 10, 10', respectively, since the spreading apart of the engagement portions required for entering the recesses may be reduced.
The holding members 111, 111' are separated by a slot 111a that may have a widened section 111b adjacent to the end portion 114. The slot 111a renders the holding members 111, 111' deflectable towards each other and apart from each other in a resilient manner. An outer surface portion 111c of the holding members 111, 111' adjacent to the cross-bars 117, 117' may be tapered in a direction such that it widens towards the cross-bars 117, 117'. When the sleeve 120 moves towards the cross-bars 117, 117' this results in compression of the holding members 11, 11' towards each other which narrows the slot 111a and brings the engagement portions 118, 118' closer towards each other.
The sleeve 120 is configured to extend around the bar-shaped longitudinal portions 113, 113' of the holding portion. It comprises a front end 120a and a rear end with a grip section 121 and an inner thread (not shown), for example in the region of the grip section 121 that is configured to cooperate with the threaded end portion 116 of the holding portion 110. Hence the sleeve 120 is configured to be moved forward and backward in the longitudinal direction by rotating it relative to the holding portion 110. When the sleeve is in the retracted position, its front end 120a has a distance from the cross-bars 117, 177' of the holding member 110 such that the tapered section 111c is at least partially exposed. An inner wall 120c adjacent to the front portion 120a of the sleeve 120 slightly tapers outward (Figs. 11a to 11d). This enables sliding of the sleeve over the tapered portion 111c. Moreover, longitudinal holes 122 may be provided in the sleeve that may serve for saving weight and/or facilitating cleaning. In a modification, the sleeve 120 may be moved forward and backward by pushing it relative to the holding portion 110.
The insertion device is configured to have a first configuration in which the engagement portions 118, 118' are spaced apart from each other at a first distance and a second configuration in which the engagement portions 118, 118' are spaced apart at a second distance smaller than the first distance. In the first configuration the sleeve is at the retracted position. By displacing the sleeve along the longitudinal axis L the slot 111a is narrowed so that the engagement portions 118, 118' are moved towards each other.
Parts and portions of the intervertebral implant and the insertion device may be made of any material, preferably, however, of a bio-compatible material, such as titanium or stainless steel or any other bio-compatible metal or metal alloy, or plastic material. As bio-compatible alloy, a NiTi-alloy, for example Nitinol, may be used. Other materials can be Magnesium or Magnesium alloys, bio-compatible plastic materials for use may be for example, Polyether ether ketone (PEEK) or Poly-L-lactide acid (PLLA). The parts can be made of the same or of different materials from one another.
Next, the operation of the intervertebral implant 1 and the insertion device will be explained. As shown in Fig. 9, the intervertebral implant is oriented with respect to the insertion device in such a manner that the front portion of the insertion device faces the front wall 2a of the intervertebral implant 1. The sleeve 120 is in the retracted position in which the tapered section 111c of the holding portion 110 is substantially free.
Fig. 10 shows the connected configuration in which the engagement portions 118, 118' have engaged the spherical recess 12 inside the recesses 10, 10'. In this configuration, the sleeve 120 has been moved towards the cross-bars 117, 117' over at least a part or most of the tapered portion 111c so that the two engagement portions 118, 118' are pressed towards each other.
Referring to Figs. 11a to 11d, the steps of engagement of the intervertebral implant with the insertion device are shown in more detail. In Fig. 11a, the insertion device is moved towards the front wall 2a with the sleeve 120 in the retracted position. In Fig. 11b the outer spherical segment-shaped ends 119, 119' of the engagement portions 118, 118' move through the opening 11 into the recesses 10, 10', respectively. As they slide along the inclined boundary walls 10a the holding members 111, 111' are slightly spread apart. As depicted in Fig. 11c, the outer ends 119, 119' of the engagement portion. 118, 118' have entered the spherical recesses 12 and clamp the implant between them. Finally, as shown in Fig. 11d, the sleeve 120 is moved towards the cross-bars 117, 117'. Since it slides along the tapered portion 111c, the holding members 111, 111' are pressed towards each other so that the outer ends 119, 119' of the engagement portions 118, 118' are firmly pressed against the wall of the recess 12. By means of this, the connection is fixed.
In the clinical use, the intervertebral implant of this type may be inserted from the anterior side. Once the intervertebral implant has been placed with the insertion device 100 between two vertebral bodies, the insertion device is be removed. This is effected by holding the holding portion 110 with the handle 30 and retracting the sleeve 120. Thereby, the clamping of the engagement portions 118, 118' is loosened and the engagement portions can be disengaged from the implant.
Since the height of the front portion 112, 112' of the insertion device is smaller than the height of the front wall 2a of the intervertebral implant 1, the visibility of the intervertebral implant during the insertion process may be improved. Also the width of the insertion device is smaller than the width of the implant which may be helpful in insertion and release of the implant.
Referring to Figs. 12 and 13, the intervertebral implant 1 is shown together with another embodiment of an insertion device. The intervertebral implant 1 in the form of an ALIF-cage has an increased functionality due to the connection portions in form of the recesses 10, 10', 30, 30'. The insertion device 200 is an insertion device which may be usually used for implants which are inserted between the vertebrae in an antero-lateral or lateral approach and require in some cases a specific angle or a variation of that angle between the insertion device and the intervertebral implant along the insertion trajectory. Fig. 12 shows the insertion device 200 engaging one of the recesses 10, 10' at the corners of the intervertebral implant. Fig. 13 shows the insertion device 200 engaging one of the recesses 30, 30' at the left sidewall or the right sidewall of the intervertebral implant.
Referring now in addition to Figs. 14 to 19, the insertion device 200 will be described in greater detail. The insertion device 200 includes a holding portion 210, a guiding sleeve 220 that receives the holding portion 210 therein, a handle 230, a rotation actuating member (not shown), and an axial position adjusting device 240. The holding member 210 is movably guided within the guiding sleeve 220 and may be advanced or retracted with respect to the guiding sleeve 220 by actuating the axial position adjusting device 240. Further, the holding member 210 may be rotated by actuating the rotation actuating member. It shall be noted that axial displacement of the holding member 210 and rotating of the holding 210 may be achieved in various other ways.
The holding member 210 defines the longitudinal axis L of the insertion device, and has a front portion which is shown in greater detail in Figs. 14 to 16. The front portion includes an engagement portion 218 with a spherical surface 219 that has the shape of a segment of a sphere. The spherical surface 219 may be formed by removing opposite segments of the sphere to yield opposite flat surfaces 219a. Hence, the engagement portion 218 has a flattened shape with a thickness between the flat surfaces 219a that is slightly smaller than a vertical height of the elongate opening 11 and heights of the openings 31 of the optional recesses 30, 30'. This permits insertion of the engagement portion 218 into the recesses 10, 10' and optionally into the recesses 30, 30' of the intervertebral implant 1, in an orientation where the flat surfaces 219a extend perpendicular to the height direction of the sidewall 2.
On at least one, and preferably on both, of the flat surfaces 219a a longitudinally extending positioning mark 219b may be provided, that extends parallel to the longitudinal axis L of the insertion device 200.
The engagement portion 218 is connected to a main portion 211 via a neck portion 212. The neck portion 212 has an outer diameter that is smaller than the maximum diameter of the spherical surface portion 219 of the engagement portion 218. The main portion 211 may have a greater diameter than the neck portion 212. The spherical segment-shaped portion 219 of the engagement portion 218 has a size such that, once the portion 218 has been inserted into the recess 10, 10' and engages the inner spherical recess 12 or into one of the recesses 30, 30' and engages the inner spherical recess 32, the holding member 210 can be tilted by 90° so that the engagement portion 218 is held in the spherical recess 12 or in one of the spherical recesses 32 but can still pivot therein.
The front portion of the guiding sleeve 220 is shown in greater detail in Figs. 17 to 19. When the holding member 210 is arranged in the guiding sleeve 220, the engagement portion 218 protrudes out of the front portion of the guiding sleeve 220. Two opposite cylindrical projections 222 form the outermost end of the guiding sleeve 220. The cylindrical projections 222 have a size such that they are insertable to the recesses 10, 10', 30, 30', respectively. An end face of the tubular guiding sleeve 220 includes a planar surface 223 and a concave, and more specifically a cylindrical surface 224 that is arranged between the two projections 222 and that has a cylinder axis which is perpendicular to the longitudinal axis L. The planar surface 223 thus forms adjacent each projection 222 an abutment surface for abutting against the second abutment surface 22 or the third abutment surface 23 at the sidewall 2 of the intervertebral implant 1 when the guiding sleeve 220 is pressed against the sidewall 2. The cylindrical surface 224 forms a small guiding surface that is configured to cooperate with guiding surface 24 at the sidewall 2 of the intervertebral implant 1 to permit a guided rotational movement of the intervertebral implant relative to the insertion device in an angular range. Hence, a radius of the cylindrical guiding surface 224 corresponds to a radius of the cylindrical guiding surface 24 on the left sidewall 2d of the intervertebral implant 1.
At an outer wall of the guiding sleeve 220 adjacent to the cylindrical projections 222 in a longitudinal direction, two opposite positioning flat surfaces 225 may be provided. The positioning flat surfaces 225 indicate the position of the cylindrical projection 222, and may serve for orienting the insertion device 200 correctly during the connection with the intervertebral implant 1. Moreover, at least one longitudinally extending positioning mark 226 at an outside of the front portion of the guiding sleeve 220 may further be provided that is 90° offset from the positioning flat surfaces 225 and that indicates the position of the projections 222.
When the holding member 210 is inserted into the guiding sleeve 220 and the engagement portion 218 projects out of the front portion of the guiding sleeve 220, the holding member 210 may be pushed forward and retracted by actuating the axial position adjustment device 240. The size of the projections 222 is such that the engagement portion 218 can only be retracted between the projections 222 in a 90° upright position of the engagement portion 218.
The intervertebral implant 1 and the insertion device may be manufactured from the same materials as described before with respect to the combination of the intervertebral implant 1 and the insertion device 100.
Next, the operation of the intervertebral implant 1 and the insertion device 200 will be explained referring to Figs. 20 to 22d. The various connection possibilities provided by the recesses 10, 10', 30, 30' increase the possibilities for surgical approaches for insertion of the intervertebral implant 1. First, with reference to Figs. 20 to 22d, an angled connection will be described in which the intervertebral implant 1 and the insertion device 200 are connected via the recesses 10 or 10' at the corner of the implant. This connection permits to adjust the angular position between the intervertebral implant 1 and the insertion device 200.
As depicted in Fig. 20, the intervertebral implant 1 and the insertion device 200 are oriented towards each other in such a manner that the engagement portion 218 faces towards the recess 10' at the corner between the front wall 2a and the left sidewall 2c. The engagement portion 218 is oriented such that the flat top and bottom surfaces 219a are substantially perpendicular to the axis of rotation R of the intervertebral implant 1. The marking 219b faces towards the upper rim of the opening 11 which facilitates the proper orientation of the engagement portion 218. As illustrated in Fig. 21, in this orientation, the engagement portion 218 can be inserted through the opening 11 into the recess 10' until the engagement portion 218 abuts against the inner wall of the spherical recess 12. Then, the engagement portion 218 is rotated until the flat surfaces 219a extend parallel or substantially parallel to the axis of rotation R. In this configuration, the engagement portion 218 is prevented from being removed through the opening 11. For locking the connection, the guiding sleeve is advanced such that the cylindrical projections 222 extend into the recess 10' through the opening 11. In Fig. 21, the flat abutment surfaces 223 of the guiding sleeve 220 abut against the flat abutment surface 23 surrounding the opening as shown for example in Figs. 2 and 3, so that the angle is between the longitudinal axis L of the insertion device 200 and the intervertebral implant 1 is about 45°. The holding member 220 is pulled backward and fixed in the pulled back position to lock the parts together. The connection may be locked by actuating a locking mechanism that holds the guiding sleeve 220 in this position.
Figs. 22a and 22b show in a cross-sectional view the relation of the intervertebral implant 1 and the insertion device 200 with respect to each other during the insertion and fixation step. Hence, Fig. 22a shows the proper orientation before inserting the engagement portion 218 into the recess 10' and Fig. 22b corresponds to the position in which the engagement portion has been rotated by 90° within the recess 12. In Fig. 22c, the connection portion 218 is rotated in the spherical recess 12 until one of the flat surfaces 219a abuts against the boundary wall 10b of the recess 10' so that the insertion device 200 extends away from the left sidewall 2c of the intervertebral implant. In this configuration, the insertion device and the intervertebral implant form an angle of substantially 0°. In Fig. 22d, the engagement portion 280 is rotated in the spherical recess 12 until the other one of the flat surfaces 219a abuts against the boundary wall 10a of the recess 10' such that the insertion device extends from the front wall 2a of the intervertebral implant 1. In this configuration, the angle between the intervertebral implant 1 and the insertion device is a little more than 90°, due to the inclination of the boundary wall 10a with respect to the front wall 2a.
Fig. 22e shows the engagement of the intervertebral implant through the additional recess 30' in left sidewall 2d. In this configuration, the implant and the insertion device can be locked together in a single position.
Generally, in use, when the engagement portion 218 is in the 90° tilted upright position, the engagement portion 218 is freely pivotable around the rotational axis R so that a plurality of angular positions of the insertion device 200 relative to the intervertebral implant can be adjusted. When the holding member 210 is retracted with the engagement portion 218 being in the upright position, engagement portion 218 presses from inside against a wall of the recess 10 or 10', so that the insertion device and the implant are pulled together. Thereby, various angular positions can be fixed. With the abutment surfaces, predefined angular positions, such as 0°, 90° or 45° as shown in the exemplary embodiment can be fixed in a form-fit manner. Intermediate angular positions may also be achieved by the aid of the guiding surfaces 24, 224 and a force-fit connection. Loosening the fixation allows adjustments to the relative position between the intervertebral implant and the insertion device without disconnecting the insertion device from the implant. This may be particularly useful for lateral or anterior approaches to the intervertebral space.
By means of the aforementioned steps and with a suitable combination of the intervertebral implant and the appropriate insertion device various access paths to an intervertebral space can be realized with one single type of intervertebral implant. In particular, an ALIF intervertebral implant may in some situations be inserted from the anterior side with the insertion device 100 and in other situations laterally using the insertion device 200.
Only by way of example, in a surgical method, access is made to the damaged disc, the disc is removed, and the intervertebral implant filled with bone graft is inserted. The spinal segment is then stabilized, for example, using pedicle screws and rods. The intervertebral implant and the insertion devices according to embodiments of the invention open a variety of possibilities to engage the intervertebral implant and to insert the intervertebral implant into the intervertebral space. Once the intervertebral implant is finally implanted in the intervertebral space, the insertion device is removed.
Referring to Figs. 23 to 37, an embodiment of the intervertebral implant and a plate assembly will be described. The intervertebral implant 1 is in this embodiment the same as in the previous embodiments. The plate assembly 300 includes a plate member 310 that is connectable via a holding member 330, a sleeve 340 and a locking member 350 to the intervertebral implant 1. The plate assembly 300 further includes bone fixation members 360 in the form of bone screws that are configured to engage the adjacent vertebrae between which the intervertebral implant 1 is sandwiched. The bone fixation members 360 each may be secured against backing out using locking members 370.
The plate member 310 will be described in more detail referring additionally to Figs. 25 to 28. The plate member 310 has an elongate shape with a top surface 310a and an opposite bottom surface 310b. It shall be understood that the plate member can have any shape, however, the elongate shape is useful for an application along the spinal column. End portions 310c, 310d of the plate member may be rounded, more specifically may have a substantially cylindrical outer contour. In addition, the plate member 310 may have a shallow curvature along its length so that it is slightly convexly shaped in a direction away from the intervertebral implant in the connected state. At a distance from the end portions 310c, 310d two holes 311 are provided that serve for guiding through the fixation members 360, respectively. The holes 311 each have adjacent the bottom surface 310b a threaded portion 311a that is configured to cooperate with a thread on the shank 361 of the fixation member 360. A side recess 311b is provided at each side of the threaded portion 311 a that faces towards the outer ends 310c, 310d. The side recesses 311b permit to orient the shank 361 of the fixation members 360 outward in an oblique manner to enable insertion into a portion of the adjacent vertebra. Adjacent to the top surface 310a each of the holes 311 comprises a recess 311c with a greater diameter than that of the threaded portion 311a which serves for housing a head 362 of the fixation member 360, respectively, and for accommodating the locking member 370. The recess 311c may have in at least a portion thereof an inner thread that cooperates with an outer thread of the locking member 370.
Between the holes 311 a central hole 312 is provided that is located substantially at the middle of the plate member 310 in the longitudinal direction. In the region of the central hole 312, the bottom surface 310b comprises a substantially flat portion 313 that may serve as an abutment for the sleeve 340. Adjacent to the abutment a first unthreaded portion 312a of the central hole 312 is formed that is substantially cylindrical and has an inner diameter that permits a portion of the holding member 330 to extend therethrough. At the opposite side a substantially cylindrical threadless recess 312b forms part of the hole 312 which has a greater diameter than the threadless portion 312a. The threadless recess 312b serves for accommodating at least a portion of the locking member 350.
The holding member 330 will be explained in detail referring additionally to Figs. 29 to 31. The holding member 330 comprises an engagement portion 338 that is shaped substantially as a segment of a sphere, i.e. it has a spherical outer surface 339 and flat top and bottom surfaces 339a. The shape of the engagement portion 338 is highly similar to the shape of the engagement portion 218 of the insertion device according to Figs. 12 to 19. Hence, the engagement portion 338 is configured to engage the recesses 10, 10' or 30, 30' in the same manner as the engagement portion of the insertion device 200. A marking 339b may be provided at at least one of the flat top and bottom surfaces 339a of the engagement portion 338. If the holding portion 330 is oriented with the marking 339b facing toward the upper rim of the opening 11 of the recess 10, the holding portion 330 is in the correct orientation for insertion. The engagement portion 338 is connected, for example monolithically, to a rod or bar 331. The bar 331 has a threaded end portion 332 opposite to the engagement portion 338. Between the engagement portion 338 and the threaded end portion 332 a thread-free section 333 is provided on which the sleeve 340 is placed. Between the engagement 338 and the thread-free section 333 of the holding member 330 a thickened section 334 may be provided that has a slightly greater outer diameter than the thread-free section 333. The thickened section 334 comprises an edge 335 from which two projections 335a, offset by 180°, extend that are configured to enter between two projections of the sleeve 340. The length of the rod portion 331 of the holding member 330 is such that when the sleeve 340 is mounted thereon, the threaded end portions 332 extends through the first unthreaded portion 312a of the central hole 312 of the plate member 310 into the recess 312b in order to be engaged by the locking member 350. At the threaded end portion 332 of the holding member, an coaxial hole 336, preferably with an internal thread, for connection an insertion device, such as a threaded rod thereto (not shown).
The locking member 350 is a nut-like member comprising a central threaded hole 351 in which the threaded end portion 332 of the holding member can be screwed. Around the central threaded hole 351 a cylindrical rim 352 is formed that has a size such that it fits into the recess 312b of the central hole 312 provided in the plate member 310. In addition, a plurality of elongate circumferentially arranged pockets 353 are provided that extend completely through the cylindrical rim 352 and that serve for engagement with a drive tool. Opposite to the lower side 352a of the cylindrical rim 352 the nut-like member comprises a cylindrical portion 354 with a smaller outer diameter. The length of this portion is such that once the locking member 350 is in the recess 312b of the central hole 312, the cylindrical portion 354 extends out of the top surface 310a of the plate member so that it can be detected more easily with a tool.
Referring to Figs. 34 to 37, the sleeve member 340 will be described. The sleeve member is configured to be placed onto the thread-free portion 333 of the holding member 330. A rear end 340a of the sleeve member 340 is substantially flat and is configured to abut against the flat surface portion 313 of the plate member 310. The front portion of the sleeve member comprises two substantially cylindrical projections 341 that are offset by 180° and configured to extend through the opening 11 into the recesses 10, 10' or 30, 30' of the intervertebral implant 1. Between the projections 341 an abutment surface 342 is formed that is configured to cooperate with an abutment surface at the intervertebral implant, for example with the abutment surface 23 in the corner of the intervertebral implant. An outer contour of the sleeve 340 may be substantially square-shaped with rounded edges. Any other contour, for example a cylindrical shape may also be possible. The projections 335 of the holding member 335 are configured to fit in-between the projections 341 of the sleeve member 340. It shall be noted that the sleeve and the plate member can also be monolithic.
In the assembled state, the sleeve 340 is mounted onto the rod-like portion 331, specifically onto the threadless 333 of the holding member 330 and the threaded end portion 332 is guided through the central hole 312 of the plate member 310 until it projects into the recess 312b. Then the locking member 350 is screwed onto the threaded end portion 332 to connect the holding member 330 to the plate member 310. For connecting the plate assembly to the intervertebral implant after the implant has been inserted into the intervertebral space, the engagement portion 338 is oriented such that the flat surfaces 319a extend substantially vertical to the axis of rotation of the spherical recess 12. Once the engagement portion 318 has been introduced into the recess 10, 10' or 30, 30' through the openings 11 or 31, the engagement portion 338 is tilted by 90° so that it cannot be removed through the openings 11 or 31. Moreover, the holding member 330 is moved backward so that the engagement portion 338 abuts against the inner wall of the recess 10, 10', 31 or 31'. The projections 335a move into the space between the projections 341 of the sleeve member 340 and thus inhibit rotation of the engagement portion 338. Thereafter, the locking member 350 is tightened with respect to the holding member 30 so that the sleeve 340 is firmly pressed with its abutment surface 340a against the flat surface 313 of the plate member and with the abutment surface 342 against the abutment surface 23 of the intervertebral implant, as depicted in Fig. 24. For manipulating the holding member 330 such as insertion into the recess 10 and rotation, a relatively thin at least partially threaded rod may guided through the locking member 350 and inserted into the threaded hole 336 of the holding member 330.
Due to the threadless connection, the plate member 310 can be easily and quickly connected to the intervertebral implant 1. In addition, various angles as in the previous embodiment can be adjusted between the holding member 330 and the intervertebral implant 1, depending on the selection of the recess 10, 10', 30 or 30'. In this way, the plate can assume various orientations with respect to the intervertebral implant which enhances the possibilities of temporary stabilization. The plate member 310 may be additionally fixed by the bone fixation members 360 which are inserted into the holes 311 and screwed into a portion of the vertebra. The locking member 370 may be used to press onto the head 362 of the fixation member 360.
In one method of use, the plate member 310 remains implanted. The plate member 310 can also serve for a temporary fixation and can be later removed. Once the bone fixation members 360 have been removed, the unlocking of the holding member 330 from the intervertebral implant 1 can be achieved easily by slightly pushing in the the engagement portion 338, tilting it and withdrawing the engagement portion from the recess 10, 10' or 30, 30'.
Fig. 38 shows a further embodiment of an intervertebral implant together with the plate assembly 300. The intervertebral implant 1' in this case is an lateral cage which is elongate and has the recesses 10, 10' for connection with the insertion device and/or the plate only on one of the short sides of the elongate implant. For example, a single recess 10 may be provided at the corner of a long side to a short side of the implant and a single recess 30 on the short side may be provided which is used in the depicted embodiment for connection to the plate member 310.
Figs. 39 to 41 show a further embodiment of the spinal implant in the form of a placeholder 1" for a vertebra or portions thereof. The placeholder comprises a cylindrical tube with a tube axis T and with openings 1a in the wall. Prongs 2 may be formed at either end to engage the end plates of the vertebral bodies between which the placeholder 1" shall be placed.
In the wall of the placeholder 1" there is an opening 11 that is elongate in the circumferential direction. The inside of the tube behind the opening 11 provides a hollow space for receiving an engagement portion of an insertion device or of a plate assembly.
As can be seen in Figs. 39 and 40, the placeholder 1" can be used together with the insertion device 200 according to Figs. 12 to 19. The engagement portion 218 is inserted in the orientation in which the flat surfaces 219a are perpendicular to the cylinder axis of the tube. After insertion, the engagement portion is tilted by 90° so that it is prevented from being removed through the opening 11. Then, the sleeve 220 is advanced to press against the outer wall of the tube and is fixed in this position. Thereafter, the placeholder 1" can be inserted between two vertebrae.
Fig. 41 shows the connection between a plate member 310' and the placeholder 1". The principle of the connection is the same as described with respect to the connection between the placeholder 1" and the insertion device. Depending on the clinical situation, a shorter holding member 330' may be used and the plate member 310' may be straight, i.e. without curvature.
Various other modifications of the spacer and/or the insertion device and/or the plate assembly may further be made without departing from the scope of the invention.
The spinal implant as shown in the above described embodiments is only an example. The contour and shape of the implant may be different according to specific clinical requirements. For example, the implant may also be in the form of a three-dimensional network or grid structure that can be manufactured, for example, by 3D printing techniques. In a further modified embodiment, the implant may be a dummy implant or testing implant that is used for a trial procedure to open the disc space before insertion of the implant that remains in the body.
The number of connection portions on the implant provided by the recesses may differ. For example, for the first embodiment it is sufficient that only one of the recesses has the specific inner shape which allows to additionally attach the other insertion device. The other one of the recesses may be shaped to only provide an abutment for the engagement portion of the insertion device.
The number, orientation, and/or abutment surfaces may vary. In some embodiments, the elongate opening can be at another position than at an edge. Still further, the elongate opening may extend vertically or at an incline. In such a case, the holding portion can be inserted in the upright orientation or inclined orientation and is then tilted. More than two elongate openings may be provided. Also, a number of additional recesses for receiving the insertion device can be more or less than that shown in the described embodiments.

Claims

An implant, in particular a spinal implant, more particularly an intervertebral implant or a placeholder for vertebrae or portions thereof, including
a body insertable into space between two bone parts or vertebrae, the body comprising a first face (5a), a second face (5a) connected to and opposite to the first face,

wherein the body comprises at least one connection portion (10, 10', 30, 30') for connecting the implant (1, 1'. 1") to a holding member (110, 210, 330) of an insertion device (100, 200) for the implant or a secondary device such as a plate member (310),

wherein the connection portion (10, 10', 30, 30') comprises a hollow space defined by the body between the first and second faces configured to accommodate an engagement portion (118, 118'; 218; 338) of the holding member, the hollow space being accessible from outside the body though an opening (11, 31) formed between the first and second faces;

wherein the opening (11, 31) is elongate such that the engagement portion of the holding device is insertable into the hollow space through the opening when the engagement portion has a first orientation and is prevented from removal from the hollow space when the engagement portion is in a second orientation; and

wherein the connection portion (10, 10', 30, 30') is located in or on the implant and configured in such a way that it permits to selectively connect at least two different holding members (110, 210, 330) to the implant.
The implant of claim 1, wherein the hollow space comprises a spherical portion (12) and wherein an axis of rotation (R) extends between the first face (5a) and the second face (5b) and through a center of the spherical portion and wherein preferably the axis of rotation is substantially parallel to a sidewall (2) that extends between the first and second faces.
The implant of claim 2, wherein the opening (11) extends around the axis of rotation (R) and has a first contour configured to facilitate pivoting of the spinal implant (1, 1', 1") relative to the holding member (110, 210, 330) about the axis of rotation to a first angular position and to a second angular position when the engagement portion (218; 338) of the holding member is in the hollow space.
The implant of claim 3, wherein the at least two different holding members are associated with at least two out of a group comprising at least two different insertion devices and a plate assembly.
The implant of one of claims 2 to 4, wherein the sidewall (2, 2a) has two corners each corner located at an end of a length portion of the sidewall and wherein the connection portion (10, 10') is located at one of the corners.
The implant of claim 5, wherein the connection portion is a first connection portion (10) and wherein a second connection portion (10') is provided at the other one of the corners preferably wherein the second connection portion is substantially mirror symmetrical to the first connection portion with respect to a plane (S) extending through a center of the sidewall between the corners and substantially perpendicular to the length portion of the sidewall (2, 2a).
The implant of one of claim 6, wherein first and second connection portions (10, 10') are configured to be engaged by a two holding members (118, 118'), respectively, that form a substantially fork-shaped holding portion (110) of an insertion device for inserting the implant.
The implant of one of claims 1 to 7, further comprising at least one third connection portion (30, 30') that is configured to be engaged by an engagement portion (218, 338) of a holding portion (210, 330) of an insertion device or a further device such as a plate assembly, wherein the connection portion is configured to be engaged so that the holding portion and the implant can form only a single angle with respect to each other.
An insertion device for inserting the implant of one of claims 6 to 8, the insertion device (100) comprising two holding members (111, 111') having each an engagement portion (118, 118') wherein the holding members form a substantially fork-shaped holding portion and wherein the engagement portions are configured to engage the connection portions at the respective corners, and wherein the holding members (111, 111') are configured to move from a first configuration in which the engagement portions have a first distance to a second configuration in which the engagement portions have a second distance from each other smaller than the first distance.
The insertion device of claim 9, wherein a sleeve (120) is provided around the holding members (111, 111') which is displaceable relative to the holding members such as to move them from the first configuration to the second configuration.
A system of an implant of one of claims 5 to 8 and an insertion device of one of claims 9 or 10, wherein in the first configuration, the holding members (111, 111') are configured to engage the connection portions (10, 10') without clamping the implant and in the second configuration the holding members are configured to engage the connection portions and clamp the implant.
A plate assembly for connecting to the implant of one of claims 1 to 8, comprising a plate member (310) and a holding member (330) connectable to the plate member wherein the holding member comprises an engagement portion (338) that is configured to engage the connection portion in a threadless manner.
The plate assembly of claim 12, further comprising a locking member (350) configured to lock the engagement portion (338) of the holding member (330) in the connection portion (10, 10', 30, 30') of the implant.
A system of a implant of one of claims 1 to 8 and a plate assembly of one of claims 12 or 13, further including a pivot inhibiting structure (335a, 341) that inhibits pivoting of the engagement portion (338) from the second configuration to the first configuration before locking when the engagement portion is in the hollow space in the second configuration.
A kit comprising an implant according to one of claims 1 to 8 and at least two out of the group comprising an insertion device (100) according to one of claims 9 or 10, an insertion device (200) having only a single holding member and and a plate assembly (300) of one of claims claims 12 or 13.